Device for truing and dressing grinding-wheels



E. R. CONNERS. DEVICE FOR TRUING AND DRESSING GRINDING WHEELS.

APPLICATION FILED NOV. 2. I917.

1,395,391. Patented Nov. 1, 1921.

2 SHEETSSHEET I.

' II-I I I 4-2- i 4/ L my? 10! [Wen/0r E. R. CONNERS.

I DEVICE FOR TRUING AND DRESSING GRIIIIDING WHEELS.

APPLICATION FILED NOV- 2, I9I7.

Patented Nov. 1, 1921.

2 SHEETS-SHEET 2.

heavy shaft 16 between said centers. Suit-' able means are provided forclamping the work to the head-spindle on which the headcenter islocated, as by a clamp 17 extending from the face-plate 18 fast on theheadspindle. Thehead-spindle is rotated by-a step-pulley 19 fastthereon.

The frame has guideways 21, 22, thereon, along which a carriage 23 isarranged to slide lengthwise of the axes of the head and tail spindles.The carriage has thereon a shaft 26, arranged to be suitably driven, asby a belt received over a' pulley 27 fast on said shaft, the shaft alsohaving releasably clamped fastthereon a grinding wheel 28 which, duringthe grinding operation, moves with the carriage, the periphery of thegrinding wheel in the present instance coacting with the surface of therotating work for grinding the latter. Suitable means are provided forthe movement of the carriage lengthwise of the work, exemplified ascomprising a screw-rod 29, journaled in suitable bearings on the frameand having threaded connection with the carriage by means of a nut 30.

The screw-rod is arranged to be rotated in opposite directions by ashaft 33, having gears 34-, 35, normally loose thereon, a clutchcollar36., having suitable spline and key connection with said shaft. Theclutch-collar is located between said gears, the said gears and saidclutch-collar having the coacting teeth of clutches 3?, 38, thereon.

Gears 4-1, 42, are fixed to said screw-shaft. The gear 35 meshes withthe gear 4-2. The gear 34 meshes with an intermediate gear 43, which inturn meshes with the gear l1. When the clutch 37 is in engagement, thescrew-rod rotates in one direction, and when the clutch 38 is inengagement, the screwrod rotates in the opposite direction, whereby thecarriage is arranged to be moved lengthwise of the work-support inopposite directions. a

Means are provided for automatically reversing the gear direction ofmovement of the carriage, accomplished for instance by means ofproviding the carriage with a tappet-lug 45, arranged to engage tappets4:6, 47, respectively adjustably secured to a tappet-bar 428 slidable inbearings d9 of the frame. The adjustments may be made by reachingthrough the front of the machineframe, which maybe open. A socket-piece51 is on the tappet-bar and has a finger 52 extending therefrom. Thefinger is pressed outwardly by a spring 53 in the socket of gagementwith either inclined face by the tappet-bar, the spring pressing thefinger along the inclined face for imparting a quick endwise movement tothe slide-bar and a quick engagement and disengagement of the respectiveclutches.

hen the carriage moves the tappet-bar in one direction, the clutch 37will become disengaged and the clutch 33 engaged, whereas, when thetappet-bar moves in the opposite direction, a reverse relation in theclutches will take place. Stoppage of movement of the carriage isaccomplished by means of a hand-lever 65, fast on the rockshaft 56, bymeans of which the clutch-collar is positioned for disengaging bothclutches, in which relation the finger 52 rests on the plane face 64 onthe slide-bar.

It is necessary for obtaining true, accurate ztnd desirable grinding,that the grinding wheel be maintained in proper grinding condition. Thegrinding wheel may in course of operation become out of true, that is tosay, its periphery or grinding surface with the material being ground,in either of which cases it isnecessary to repair the grindlng surfaceof the grinding wheel.

For accomplishing this, 1' provide abrading wheel, preferably anabrading wheel ofcomparatively small diameter, of a texture much harderthan the texture of the grinding wheel to be trued or dressed, andprovide means for rotating said abrading wheel at a high peripheral rateof speed, preferably so that the abrading wheel will, in thegrinding-wheel contacting portion of its peripheral path,move in adirection opposite to the direction in which the abrading wheelcontacting portion of the periphery of the grinding wheel moves. Iprefer to employ a carborundum abrading wheel.

I further provide means whereby relative axial movement takes placebetween the abrading wheel and grinding wheel during the truing ordressing operation, and l preferably provide means, which may beemployed if desired, whereby the grinding wheel may be dressed duringthe grinding operation.

Referring again to Figs. 1 and 2., means nee are provided for adjustingthe distance between the grinding wheel and the work, exemplified asaccomplished by mounting the bearings of the shaft of the grinding wheelon a slide 66, adjustable crosswise of the carriage on guides 67, as bymeans of an adjusting screw 68, journaled in the carriage and havingthreaded connection with the slide by means of a nut 69 fixed to theslide. A clamp-bolt TO secures the parts in ad justed positions.

Exemplifying iny improved device as applied to a grinding machine havinga workcarriage, and referrng to Figs. 3 and a, parts are. shown similarto Figs. 1 and 2, with the difference that the work is mounted on acarriage so as to move lengthwise in opposite directions with relationto the grinding wheel, which is stationarily located, but havingadjustment toward and from the work by being mounted on a slide to movetransversely to the direction of movement of the work-carriage. Tn thiseireniplification, the parts are designated by reference numeralssimilar to the reference numerals applied to the parts in Figs. 1 and 2,raised to the series 100, the screw having connection with theworlocarriage for moving the carriage lengthwise of the axis of rotationof the grinding wheel, and the tappet-bar being operated by thework-carriage.

The aorading wheel of my improved device is designated by the numeral75. This abrading wheel is represented as a cylindrical ahrading wheelcoasting vith the cylindrical grinding wheel.

The apraoing' wheel 18 shown releasably secured a haft 76, which isjournaled in a bearing; 1?"? comprising a bushing 78. (See Figs. 5, 67.) The bushing is a split bushing, as shown by the split 79. lt-s outerperiphery is tapered, received in a tapered bore 80' of the outerbearing-member. The bushing has a threaded end 81, over which a nut 82is received for clamping the bushing firmi in said bore. TV hen thebushing is worn, it is drawn endwise by said nut for contracting itsshaft-contacting inner periphery so that an accurate bearing surfacebetween the shaft 'Ziland its hearing may be always maintained. Thebushing is prevented from turning by screws 88 in the outer memberreceived a slot 8 in the he hing.

The hearing 77 is secured to a support 85, shown in the form of abearing-ring, a setholt 86 clamping bearing-ring to the hearing,

l he ahrading-wheel support is adjustably secured to the worlr support,as by providing the bea 'ig-ring with a stern 87 projecting therei' Thestern is arranged to be received -ii unfi l d in a lug 89 on thetail-stock Ii, 2 and 5, in a 109 in the tail-stool;

a suitable aperture 88.,

T" u 4.47., id 1gb, O

- diameter 'th 1 1 wheel and o soi 11 1- in Figs. 8 and i, the sternlacing ranged to be clamped in ad usts i positions in its bearing bymeans or a set-colt 90 in Figs. 1, 2 and 5, and by a set-bolt 190 inFigs. 3 and The shaft 76 is provided with an annular shoulder 91,forming a flange thereon having end bearing on the bushing, for limitingendwise movement of the shaft in one direction in the hearing. The otherend of the shaft is provided with a reduced part "forming a shoulder 92,against which a washer 93 is received, the washer bearing; against theother end of the bushing. The abrading wheel 75 is received between thewasher 93 and a washer a4, a nut 95 clamping the abrading wheel to theshaft between sail washers, being received over the threaded end of thereduced portion of the shaft, represented as provided with a left-handthread, assuming that the abrading wheel is arranged to rotate in aright-hand direction.

The abrading wheel is indicated as rotatingz in the direction of thearrow (1, the grinding wheel being instanced as rotating in thedirection of the arrow Z), and the work as rotating in the direction ofthe arrow 0.

An electric motor 96 is provided, and is instanced as comprising acasing 9! and an armature-shards 88. The bearin W is pro vided withlaterally es 99, arranged to be secured to e webs 100 of the casing oithe motor by screws 101. T innor end of the bearing is provider borereceived over tloi tnxnble 102 about the bearing 103 of the arnaatuneshThe arrna ire-shaft is exemplified ii hly connected with theabrading-wheel sh instanced as accomplished by providing tooth-clutch104 between the proximate ends of said shafts, the respective clutclbeing on said respective shafts.

My improved device is such saving in the durability of wheel isaccomplished and the Oil the grinding; wheel is enhanc' plished by theabrading wheel d brushing the foreign substances out recesses and poresin the grinding surf-a the grindi 55 wheel and presen to the grinding;wheel which en danger of gouging into th The abrading wheel is of subs'11 the diameter of the wheel so that the drawing or brusi t ereof maybe ei'lective.

in my ture is free to move axially between the fields of theelectricmotor, so as to automatically follow the lines of electric forceand utilize the motor capacity.

If desired, the abrading wheel may be adjusted to contact the grindingsurface of the grinding wheel, preferably with only slight pressure,alternately with the contacts of the rinding wheel with the work. formaintaining the grinding surface of the grinding wheel in accuratecondition.

Having thus fully described my invention, what I claim as new and desireto secure by Letters Patent, is:

1. In a device of the character described; the combination of awork-support, a support for a grinding wheel, means for causing movementbetween said supports lengthwise of the axis of rotation of saidgrinding wheel, an abrading wheel for truing said grinding wheel, saidabrading wheel mounted on said work-support, and an electric motormounted'on said work-support for rotating said abrading wheel, saidgrinding wheel arranged by said movement between said supports to bebrought into coactive relation with both the work on said work-sup= portand said abrading wheel during maintenance of position of said grindingwheel on its support.

2. In a device of the character described, the combination of awork-support, a support for a grinding wheel, an abrading wheel for thegrinding wheel, a support for the latter mounted on said work-support,and an electric motor mounted on said support for said abrading wheelhaving a flexible drive-connection with said abrading wheel, saidgrinding wheel arranged by said movement between said supports to bebrought into coactive relation with both the work on said work-supportand said abrading wheel during maintenance of position of said grindingwheel on its support.

. 3. In a device of the character described, the combination of arotatable grinding wheel, a shaft, a rotatable abrading part attached tosaid shaft for coacting with said grinding wheel in order to surface thegrinding surface of said grinding wheel, an electric motor for drivingsaid shaft, means for fixing said shaft endwise the axes of rotation ofthe armature-shaft of said electric motor'and said shaft beingsubstantially coincident, said shafts having a flexible drivingconnection between them for axial movements of said armature-shaftrelative to said first-named shaft, and means for causing feedingmovement between said grinding wheel and said abrading wheel lengthwiseof the axis of rotation of said grinding wheel. 7

4. In a device of the character described, the combination with awork-support and the support of a grinding wheel, rotating means on saidwork-support for rotating the work, means for causing movement betweensaid supports lengthwise of the axis of rotation of said grinding wheel,an ,abradingwheel support provided with a stem, means for securing saidstem on said work-support, a shaft journaled in said abrading-wheelsupport, an abrading wheel secured to said shaft, an electric motorhaving support on said abrading-wheel support, and a flexible driveconnection between the armatureshaft of said motor and said shaft ofsaid abrading wheel, the said rotating means for the work, said grindingwheel and said abrading wheel being so related that upon said movementbetween said supports said grinding wheel may coactwith both said workand said abrading wheel during maintenance of its position on itssupport.

5. In a combined grinding and truing machine, the combination of awork-support, a grinding-wheel support, an abrading-wheel support, meansfor adjustably securing said abradingwheel support to said work-support,a shaft journaled in, said abradingwheel support, an abrading wheelsecured to said shaft, an electric motor supported by saidabrading-wheel support, and means for causing movement between saidworksupport and grinding-wheel support lengthwise of the axis ofrotation of said grinding wheel for coaction of said grinding wheel withthe work on said work-support and with said abrading wheel duringmaintenance of position of said grinding wheel on its support.

6. In a combined grinding and truing machine, the combination of awork-support, a grinding-wheel support, a grinding wheel thereon, asupport for a rotatable abrading part, a rotatable abrading partthereon, means for adjusting said grinding wheel and said rotatableabrading part in directions transverse to the axis of rotation of thework at opposite sides of the lines of contact between the grindingwheel and the work and between the rotatable abrading part and thegrinding wheel, in order to locate the peripheries of said work andsaid. rotatable abrading' part at the cylindrical projection of saidgrinding wheel, and means for causing movement between said supportslengthwise of the axis of rotation of said grinding wheel for causingalternate contacts between the grinding wheel and the work and betweenthe rotatable abrading part and the grinding wheel during maintenance ofposition of said grinding wheel on its support.

7. In a combined grinding and truing ma- -chine, the combination of awork-support,

rotating means thereon for rotating the work, a support for a grindingwheel, rotating means thereon for said grinding wheel, a rotatableabrading part mounted on said work-support and arranged for coactionwith said grinding wheel, means for rotating said rotatable abradingpart, and means for causing movement between said supports lengthwise ofthe axes of rotation V rotating means thereon for rotating the work, asupport for a grinding wheel, ro-

tatin means for said grinding wheel, a rotatab e part mounted on saidwork-support, rotating means for rotating said rotatable abrading part,and means for causing movement between said supports lengthwise of theaxis of rotation'of said grinding wheel for selectively causing coactionbetween said rotatable grinding wheel and said rotatable work andbetween said rotatable abrading part and said rotatable grinding wheelwhile the angularrelations and distances between said axes of rotationare maintained.

9. In a combined grinding and truing machine, the combination of awork-support,

rotating means thereon for rotatin the work, a support for a grindingwhee, ro-

tating means thereon for said grinding wheel, a rotatable abradingpartmounted on said work-support and arranged for coaction with saidgrinding wheel, an electric motor mounted on said work-support forrotating said rotatable abrading part, and means for causing movementbetween said supports lengthwise of the axes of rotation of said firsttwo named rotating means for selectively causing coaction betweensaidrotatable grinding wheel and said rotatablework, and between saidrotatable abrading part and said rotatable grinding wheel.

10. In a combined grinding and truing machine, the combination of awork-support, rotating means thereon for rotating the work, a supportfor a grinding wheel,

rotating-means thereon for said grinding wheel, a rotatable abradingpart mounted on said work-support and arranged for coaction with saidgrinding wheel, an electric motor. mounted on said work-support forrotating said rotatable abrading part, means for causing movementbetween said supports lengthwise of the axes of rotation of said firsttwo named rotating means for selectively causing coaction between saidrotatable grinding wheel and said rotatable 'work and between saidrotatable abrading part and said rotatable grinding wheel, the axes ofrotation of said rotatable abrading part and the armature shaft of saidelectric motor being substantially parallel, and flexible drivingconnection between said armature shaft and said rotatable abrading part.

11. In a device of the character described, the combination of awork-support, a support for a grinding wheel, an emery grinding wheel onsaid last-named support, means for causing movement between saidsupports lengthwise of the axis of rotation of said grinding wheel, acarborundum abrading wheel mounted on said work-support, saidcarborundum abrading wheel having a texture much harder than the textureof said grinding wheel, said grinding wheel arranged by said moveinentbetween said supports to be brought into coactive relation se- .portslengthwise of the axis of rotation of said grinding wheel, a carborundumabrading wheel mounted on said work-support, said carborundum abradingwheel having a texture much harder than the texture of said grindingwheel, and constructed and arranged whereby to draw foreign substancesout of the recesses in the grinding surface of said grinding wheel, forthe purpose described.

13. In a device for truing and dressing grinding wheels, the combinationof a worksupport, rotating means thereon for rotating the work, asupport for a grinding wheel. rotating means thereon for said grindingwheel, a rotatable abrading part mounted on said work-support andarranged for coaction'with said grinding wheel, means mounted on saidwork-support causing maintenance of rotation of said abrading part, andmeans for causing movement between said supports lengthwise of the axisof rotation of said grinding wheel for causing alternate coactionbetween said rotatable grinding wheel and said rotatable work andbetween said rotatable 'abrading part and ,said rotatable grindingwheel.

